How Much Electricity Tesla Cars Use
Photograph (CC0) by Theodor Vasile, cropped by Larry Neal Gowdy
Copyright ©2021 - May 25, 2021
Quick Answer
As is given with more details in How Much Electricity Does an Electric Car Use - Part 1, multiply the electric car's kWhr (kilowatt-hour) battery rating by 5. The sum will be near to how much energy from a power plant that a Tesla electric car consumes in-between each full charge. Then multiply the summed quantity of kilowatt-hours by 2 to sum a rough national average of how many gallons of water were consumed to generate the electricity.
Example: A 50kWh battery rating multiplied by 5 equals 250kWh consumed. 250 multiplied by 2 equals 500 gallons of water consumed.
If a Tesla car is able to drive 200 miles on a fully charged 50kWh battery, then dividing 250 (total kwh energy used to charge a 50kWh battery) by 200 miles sums to approximately 1.25. Multiplying 1.25 by 2 gallons of water per kWh equals an average of about 2.5 gallons of water consumed per mile. At 60mph, the Tesla car will consume about 150 gallons of water per hour.
If there were 1,000,000 electric cars traveling at 60mph, then the electric cars would consume about 150,000,000 gallons of water every hour.
If the average mileage of all vehicles were 20,000 miles per year, then each electric vehicle would consume about 50,000 gallons of water per year. If the USA were to only use electric vehicles, then roughly 300-million electric cars would consume about 15,000,000,000,000 (15-trillion) gallons of water every year.
Water use in the USA is currently around 40% for agriculture and around 40% for electricity. If the USA were to only use electric cars, then the quantity of water used in the USA would increase another approximated 20% to 40%. The USA does not have that much water to waste.
Tesla Electric Cars CO2 Emissions
As further explained in How Much Electricity Does an Electric Car Use - Part 2, at 22,000 miles a year, an electric car emits about 9,980 to 11,579 pounds of CO2 (from the electric power plant) while consuming about 55,000 gallons of water. For the same distance, a 35mpg economy gasoline powered car would emit about 12,300 pounds of CO2, and a 40mpg economy gasoline powered car would emit about 10,800 pounds of CO2, with neither gasoline powered car consuming additional water.
Forming estimates based upon the most efficient forms of fuel-based electricity generation, electric cars emit similar quantities of CO2 as do economy gasoline powered cars. Based upon less efficient forms of electricity generation (i.e. coal powered plants), economy gasoline powered cars may emit about half as much CO2 as electric cars. Based solely upon hydroelectric electricity generation, electric cars may not emit much CO2, but the costs of water consumption and environmental destruction is extremely huge and permanent. Wind generation of electricity has advantages of not needing much fuel and water, but wind power alone cannot provide a continuous supply of electricity to the grid: power plants remain a necessity. Nuclear powered plants use about 65% more water than natural gas powered plants, plus leave radioactive wastes that permanently pollute the environment.
Regardless of which source that an electric car draws its electricity, the end result is never superior than the use of gasoline powered vehicles.
Basic Physics
As is common on the forums populated by Tesla owners, the claim is that their electric cars draw around "300" to "340" watts per mile. If the claims were true, and if their electric cars are so efficient, then the owners could mount a little 400-watt wind generator on the roof and then have a perpetual motion device. The laws of physics — laws of thermodynamics and conservation of energy — state that it is impossible to create a perpetual motion device (especially not one that is based upon mechanical power).
"300" watts equals the amount of electricity to power five each 60-watt light bulbs. "340" watts equals five each 60-watt light bulbs plus one 40-watt light bulb. It is utterly impossible to propel a 4,000 pound vehicle at highway speeds with only 300-340 watts of energy, and likely not even enough to drive an electric car out of a flat driveway within several seconds.
Horsepower: A 2,000 pound vehicle with about 15 square feet of frontal area will need approximately 15 horsepower to travel at 70mph. A 3,000 pound vehicle with approximately 20 square feet of frontal area will need approximately 20 horsepower to travel at 70mph. A typical 4,000 pound lithium battery powered electric vehicle with approximately 20 square feet of frontal area will need approximately 30 horsepower to travel at 70mph.
As quick comparisons, a 1960 MGA roadster at 2,000 pounds only needs around 15 horsepower to maintain 70mph, while a new 4,000 pound Tesla electric car consumes about twice the power and energy to perform similar work. Twice the power consumed results in twice the heat emitted. Buying an electric car that consumes double the power does not result in energy savings, nor save the planet.
Horsepower as Wattage: Of the precious few specifications found, Tesla cars are indeed reported to weigh about 4,000 pounds. The simple mathematical formula is that 1 horsepower equals about 746 watts of electricity. Therefore, a continuous 30 horsepower continuously requires about 22,380 continuous watts of electricity. Similar to a 60-watt light bulb continuously consuming 60 watts, so do all other electrical devices continuously consume electricity while the electrical devices are in operation.
Tesla electric batteries are reported to be rated at 350 to 400 volts. If about 22,380 watts of power are needed to propel a Tesla car at 70mph, then a 350v battery would be discharged at about 63.94 continuous amps. A 400v battery would be discharged at about 55.95 continuous amps. It would seem impossible that anyone could sincerely believe that an electric car could travel at any reasonable speed while only consuming 300 to 350 watts of electricity.
I myself struggled with the attempt to rationalize why at least some Tesla owners believe that their electric cars are able to defy all laws of science, defy all laws of Nature, and defy commonsense itself. Finally I reasoned that the alleged wattages were the actual wattage divided by miles driven. I then found a photograph of a Tesla interior display that showed "234 Wh/mi". Other examples included: "Since 7:00 PM /// 64.8 mi / 1:47 hr / 234 Wh/mi /// Since last charge 139.8 / 34 / 243". Aha! So then the Tesla owners may have indeed believed that the "234 Wh" was an actual wattage, and not the factual wattage divided by the miles driven.
Another Tesla display photograph shows "Avg. 414 Wh/mi Past 30 mi". Allegedly, the "414 Wh" could be multiplied by 30 to derive 12,420wh, which would sum to about 16.65 horsepower, which ought to be sufficient enough to travel at median city speeds.
Dividing wattage by miles is like placing an "Alive" meter on someone, and the meter displaying "20% Alive". No, people are continuously 100% alive until dead. The same goes for wattage: the wattage is continuously 100% of volts times amperes until the electrical device is turned off.
For whatever reasons, Tesla chose to use non-standard wattage read-outs, which has confused a lot of people (including myself).
Without the firsthand experience of driving and recharging a Tesla electric car, and without there being schematics and wiring diagrams available, the only option available is to make generalized estimates based upon known physics and the averages of similar devices that were measured firsthand, which is what the series How Much Electricity Does an Electric Car Use does.
Core Environmental Impacts of Tesla Electric Cars
[1] Lithium: Mining for lithium is expensive, requires large quantities of water, and severely damages the environment. Recycling lithium is expensive, requires more energy for heating, and the toxic wastes severely damage the environment further.
According to various reports, a typical Tesla electric car battery has about 26.5 pounds of lithium. Large quantities of water are required to extract lithium from the ground. According to averaged estimates, about 66,225 gallons of water are used for each Tesla battery.
Lithium-rich areas like Chile are said to now be suffering from a lack of water for agricultural regions due to the mining of minerals like lithium. Food and human life are more important than an electric car. Too, regardless of how lithium is mined and recycled, the result is always an intense pollution and destruction of the environment.
Imagine a world twenty years from now, struggling to dispose of tens of millions of toxic lithium car batteries each year. It is useful for an individual to research the toxicity of lithium-ion batteries.
[2] Copper: The increased use of copper for electric motors will result in higher prices for all products that use copper. The products include computers, appliances, housing, plumbing, and most every other product bought and consumed by most citizens. Regardless of whether an individual owns an electric car or not, the average citizen will pay a percentage of the costs to build electric cars.
[3] Battery Hazards: Aside from exploding and self-combusting lithium-ion batteries (Chevrolet, Dell, Samsung, Tesla, et al), there is also the health hazard of gas emissions from lithium-ion batteries. Fuels burn; lithium-ion batteries are incendiary devices. In the 1970s the Ford Pinto suffered from fires caused by ruptured fuel tanks when some of the cars were rear-ended. The Pinto fix was relatively easy; simply move and better protect the tank. Lithium-ion batteries cannot be protected from themselves.
[4] EMF Health Hazards: Everyone is different, and everyone has different levels of sensitivity to EMF (electromagnetic force) fields, but one of the common sensitivites is from the high field strengths of electric motors. Generally, 120v electric motors do not cause much sensitivity, but as the voltages increase, so does sensitivity increase. It is relatively common for people to be sensitive to the fields emitted by 400v electric motors. Electric motors in electric cars are reported to have operating voltages in the 400v range.
Tesla cars also incorporate several different microwave devices that emit EMF inside and outside of the vehicles. The percentages are difficult to establish, but a general observable average is that roughly half of all people are measurably negatively influenced by microwave fields. Late model gasoline powered cars also now include the purposeful emissions of microwave frequencies within the cars' metal cabins, which traps and encapsulates the occupants within microwave EMF.
Being encapsulated within an electric vehicle is harmful to health and mind. Experienced electronic techs and mechanics also know that all devices fail in time. A gasoline powered car can limp home on half of its cylinders. An electric car will be dead on the road when a voltage regulator fails. Electric vehicles cannot be trusted during emergency situations, nor are electric vehicles useable during prolonged power outages.
Sum
Electric cars have no real-world advantage over gasoline powered cars, but rather electric cars pose a far greater threat of global warming and destruction of the environment as compared to gasoline powered cars.
If an individual is mindful of the environment, then the better choice would be to simply drive fewer miles and to use less electricity. Buying an electric car is not an answer to global warming.